JP5450613B2 - Chemical mechanical polishing with slurry delivery to multiple zones - Google Patents

Description

  This application relates generally to chemical mechanical polishing / planarization (CMP). More particularly, this application relates to CMP apparatus and techniques that involve delivering a slurry or other fluid to multiple zones.

  Chemical mechanical polishing (CMP) is the process of removing material from a semiconductor wafer or other workpiece to create a smooth plane. Typically, a combination of chemical reaction and mechanical force is used to remove material from the front surface of the workpiece, thereby creating a flat surface. In conventional CMP assemblies, the workpiece is secured to the carrier head so that the surface to be polished is exposed. Next, the exposed surface of the workpiece is generally held against a polishing pad, i.e., a mating surface, placed on a rigid platen. Generally, a polishing slurry is introduced into the polishing surface of the pad, and the workpiece and / or polishing pad is linear, circular as necessary for polishing or planarizing the surface of the workpiece. Move relatively in an annular or other manner.

  Slurry is often supplied to the polishing surface through one or more holes in the polishing pad. These holes typically receive fluid from a fluid source via a common delivery line. In many implementations, a manifold or similar structure equalizes the fluid resistance for the various paths that flow through the different holes. Although the manifold structures found in many implementations have been beneficial for many purposes, the complex design of such structures tends to create certain limitations and other problems. In particular, the number of holes that can be supported by any manifold is relatively limited, which can cause problems with slurry distribution and / or the creation of a uniform flow across the surface of the polishing pad.

  Accordingly, it is desirable to create a polishing structure and method that can increase the uniformity of slurry delivery across the surface of the pad. Furthermore, other desirable features and characteristics will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings, the foregoing technical field and background.

  In various embodiments, chemical mechanical polishing or planarization (CMP) of the workpiece is enhanced by slurry delivery to multiple zones. A polishing pad is provided in contact with the workpiece and a multi-zone platen is displaced proximate to the polishing pad to facilitate slurry delivery. The platen includes a plurality of fluid distribution layers, each of which includes a fluid distribution path that extends from a fluid source to a distribution point on the layer. Each distribution point of the fluid distribution layer corresponds to a different location on the polishing surface, thereby forming a plurality of fluid delivery zones in the pad.

  In another embodiment, a platen for use in chemical mechanical polishing of a workpiece is provided. The platen includes a first fluid distribution layer including a first path that extends radially from a first fluid source to a first distribution point, and a second fluid distribution layer proximate to the first distribution layer. And a second fluid distribution layer including a second path extending radially from a second fluid source to a second fluid distribution point, the second fluid distribution layer further comprising the second fluid distribution layer. A hole corresponding to the first distribution point in one fluid distribution layer. An expansion layer is disposed proximate to the second distribution layer, the expansion layer including a first passage hole that coincides with the hole of the second fluid distribution layer, and the second fluid distribution point. And a second path hole that coincides with.

  In yet another embodiment, a method is provided for chemically mechanically polishing a workpiece using a platen having a plurality of slurry delivery zones. The method includes initiating chemical mechanical polishing of a workpiece to provide slurry to the workpiece through each of a plurality of slurry delivery zones, and during the chemical mechanical polishing of the workpiece Adjusting the amount of slurry supplied through the delivery zone for each of the slurry delivery zones.

  In the following, various embodiments will be described with reference to the following drawings, in which like numerals indicate like elements.

1 is a cross-sectional view of a typical CMP apparatus having multiple slurry delivery zones; 2 is a plan view of an exemplary platen assembly for a CMP apparatus showing multiple slurry delivery zones; FIG. 3 is an exploded perspective view of an exemplary platen assembly for a CMP apparatus that provides multiple slurry delivery zones; FIG. 2 is a plan view of an exemplary expansion structure for slurry delivery; FIG. 2 is a perspective view of an exemplary plug capable of supplying slurry to multiple delivery zones; FIG. 3 is a cross-sectional view of an exemplary plug capable of supplying slurry to multiple delivery zones; 2 is a side block diagram of an exemplary controlled delivery system showing slurry delivery to multiple zones of a polishing pad; 6 is a flowchart of an exemplary process for polishing a workpiece using a plurality of zone CMP apparatuses.

  The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, summary of the invention or the following detailed description.

  In accordance with various exemplary embodiments, a new structure and method for chemical mechanical polishing / planarization is provided, which creates a number of slurry delivery “zones” on the polishing pad. Make it possible. Slurry fluid can be provided and controlled independently for each zone to reduce slurry flow rate variation across the pad or to deliver different flow rates to different zones during polishing. In various embodiments, the multiple slurry delivery zones are implemented by a multi-layer platen assembly that distributes the slurry separately from the different supply lines to the various zones. Such a structure can provide better slurry coverage than conventional structures across the surface of the pad or workpiece. Further, by providing and controlling slurry delivery independently to the various zones of the platen or pad, an increased uniformity of slurry delivery can be established and / or across the pad. The effectiveness of the dispensed slurry allows adjustment across the pad surface to better control the radial thin layer realized at various points at the pad / workpiece interface.

  Many terms are clarified first. For example, the terms “polishing” and “planarization” sometimes have different meanings, but are often used interchangeably by those skilled in the art. For ease of explanation, in accordance with such common usage, the term “CMP” is equivalent to either “chemical mechanical polishing” or “chemical mechanical planarization”. The terms “polishing” and “planarizing” are also used interchangeably herein. In addition, the terms “chemical mechanical polishing / planarization” and CMP broadly refer to equivalent techniques with similar capabilities and / or requirements for uniform removal of material from a workpiece, such as electrochemical mechanical polishing (ECMP). Intended to include. The term “fluid” is intended to include any liquid, gas, or any other substance capable of flowing through a passage. Examples of fluids include slurries, chemical solvents, vapors, mists, air or other atmospheric vents, mixed fluids, gases or liquids under pressure or vacuum, vapors and / or all other forms of material. Including. Further, the term “typical” is given meaning in the context of an example and may or may not be used as an example. That is, a “typical” embodiment is only intended as an example of an embodiment having any alternative and / or additional embodiments or features different from those described herein.

  Turning now to the drawings, FIG. 1 shows an exemplary CMP apparatus 100 that includes a spindle assembly 102 coupled to a carrier head 106 via a shaft 104. The carrier head 106 is designed to receive a wafer or other workpiece 108 and to support the workpiece 108 against the polishing pad 110 or other surface during planarization. In various embodiments, the shaft 104 extends and contracts outward (eg, vertically as shown in FIG. 1) to apply pressure to the back surface of the workpiece 108, thereby processing against the polishing pad 110. The object 108 is pressed. In an equivalent embodiment, the workpiece 108 is maintained in a substantially fixed position, and the pad 110 is displaced by a motor / shaft device or other structure, thereby causing a pressure between the pad 110 and the front surface of the workpiece 108. Is made. Typically, a motor or other structure within the spindle assembly 102 rotates the shaft 104 and the carrier head 106 to create a rotational movement between the workpiece 108 and the polishing pad 110. In various embodiments, the spindle assembly 102 also creates strays, vibrations or other movement of the workpiece 108 relative to the polishing pad 110 as needed.

  The platen assembly 112 mechanically supports the polishing pad 110 and, in many embodiments, supplies slurry to the polishing interface between the polishing pad 110 and the workpiece 108. The platen 112 optionally includes a multi-layer fluid delivery system comprising slurry supply holes and / or discharge holes or passages provided to deliver slurry to and / or remove slurry from the upper surface of the polishing pad 110. Can do. During a conventional polishing operation, the pad 110 rotates and / or annularly moves about the platen axis 125 while the carrier head 20 simultaneously rotates the wafer 21 about the carrier head axis 123. In a typical CMP process, the carrier head axis 123 is generally offset from the platen axis 125 by a distance referred to as the upper-to-lower head offset. Further, in various embodiments, the entire platen assembly 112 can circulate around the carrier head axis 123 or other points, if desired. This orbiting motion can be provided by an arm 114 or other structure that couples the platen assembly 112 to a motor or the like.

  During the polishing process, the slurry is delivered via platen 112 to one or more polishing zones 115, 116, 117, 118 as described more fully below. 1 shows various exemplary zones 115-118 in side view, while FIG. 2 shows the same exemplary zones 115-118 in a view from above. In the example shown in FIGS. 1 and 2, four typical zones 115, 116, 117 and 118 are shown as concentric annular regions. However, in other embodiments, any number of zones 115-118 may be provided, and each zone may have any shape or dimension with respect to other zones. In some embodiments, for example, providing a number of relatively narrow zones corresponding to the outer edge of the workpiece 108 can be beneficial as this can provide additional control over edge conditions during planarization. It may be. Slurry delivery zones 115-118 can be designed, for example, to correlate with carrier pressure zones or to mitigate uneven polishing due to edge burns and / or other effects. Embodiments equivalent to those shown in FIGS. 1-2 can thus provide any number of independently controlled slurry delivery zones 115-118, which can be any Concentric or non-concentric schemes can be formed, and the size can be set by any regular or irregular arrangement as required.

  The slurry can be discharged from the surface of the workpiece 108 by any method. In various embodiments, the polishing surface of the pad 110 is provided with a set of grooves or other topographic features to distribute the flowable slurry across the surface of the pad 110 during planarization. These features, as well as the relative motion kinematics between the workpiece 108 and the pad 110, can effectively guide the movement of the slurry particles during polishing in any desired manner. Drain holes or other passages can also be provided in the pad 110 and / or the platen 112 for recovery of used slurry. Although any other fluid dispensing and / or draining method can be applied equivalently to other embodiments, an example of a fluid dispensing system that provides a relatively uniform distribution of fluid across the surface of the pad 110 is Similar to discharge, it is described in US Pat. No. 6,918,824.

  During operation of the CMP apparatus 100, the slurry can be independently controlled for delivery to each of the zones, thereby substantially stabilizing across the interface between the pad 110 and the workpiece 108. The slurry flow can be enabled or the slurry flow in one or more zones 115-118 can be adjusted with respect to the slurry flow in any other zone. For example, the slurry flow can be controlled using a digital microprocessor, microcontroller, etc. to independently adjust the slurry flow rate to one or more zones 115-118 as needed. . The slurry flow can be controlled by any method. In various embodiments, a common slurry delivery line can pass through, for example, a single valve, opening, or other type of fixed or variable restrictor per zone. In other embodiments, slurry delivery lines can be provided in every two or more zones, with each delivery line having its own flow controller. Various methods and structures for performing multi-zone slurry delivery are described more fully below.

  For example, in the exemplary embodiment shown in FIG. 3, one type of multi-layer laminated platen assembly 112 includes a base or support layer 302, an appropriate number of fluid distribution layers 310, 320, 330, and an extension. Layer 340 as appropriate. The laminate assembly 112 is provided proximate to the polishing pad to distribute slurry or other fluid to the polishing pad 110. In various embodiments, the platen 112 also includes a central plug 352, as described more fully below.

  The base or support layer 302 can take any structure that supports the fluid distribution layers 310, 320, 330 as desired. Layer 302 as shown in FIG. 3 includes any number of holes 303 for matching slurry discharge, as well as the arrangement of vortex probes, endpoint detection probes and / or the like. Layer 302 also includes a central hole 304 that can accommodate plug 352. In various embodiments, there is no base layer 302, and the first layer of the laminated platen assembly 112 includes a fluid distribution path or other structure, as appropriate.

  Each fluid distribution layer 310, 320, 330 is suitable for distributing slurry or other fluid from a fluid source (eg, plug 352) to one or more fluid distribution points 317, 327, 337 (respectively). Fluid distribution paths 312, 322, 332 are included. Paths 312, 322, 332 represent any type of groove, tube or other passage in fluid distribution layer 310, 320, 330 that may guide slurry or other fluid. Although FIG. 3 shows various paths formed in the relative “top” surface of layers 310, 320, 330, equivalent embodiments include grooves or other paths on the opposite side of the layers. And can also include a passage formed in the layer. Further, the path formed in any fluid distribution layer 310, 320, 330 may be formed in a fluid source, path and / or adjacent layer to guide the fluid in any manner toward the desired polishing zone. Can cooperate with other structures.

  The fluid distribution passages 310, 320, 330 may take any shape or size. In the embodiment shown in FIG. 3, fluid distribution points 317, 327, 337 simply represent the end points of fluid distribution paths 312, 322, 332. In many embodiments, these endpoints can be primary points for distributing slurry or other fluid away from the fluid distribution layer and toward the polishing pad 110. Each fluid distribution layer 310, 320, 330 may be adapted to flow from the underlying fluid distribution points 317, 327, 337 toward the polishing pad 110, and as required, with fluid ejection and probe placement and / or other Any number of holes or other passages can be included to accommodate the elements. For example, layer 320 is shown with holes 325 that coincide with distribution points 317 on layer 310. Layer 330 is also shown with holes 335 corresponding to distribution points 317 on layer 310 and holes 336 corresponding to distribution points 327 on layer 320. Further, each layer 310, 320, 330 has holes 314, 324, 334 (respectively) in a generally central location or other location suitable to accommodate the fluid source 352, as will be fully described below. Including.

  Each fluid distribution layer 310, 320, 330 shown in FIG. 3 corresponds to one or more delivery zones 115-118 as shown in FIG. 1-2. Layer 310 includes, for example, a fluid passage 312 to a distribution point 317 that extends generally away from the fluid source 314 and near the outer edge of the platen 112. Layer 330, in contrast, includes a fluid passage 332 that extends to a distribution point 337 that is located closer to the central fluid source 344 and further away from the outer edge of the platen 112. Layer 320 includes a fluid passage 322 that extends from a fluid source 352 to a distribution point 327 located at a midway position between passages 317 and 337 at a radial distance on the platen 112, in this embodiment the fluid source is The platen 112 is disposed approximately at the center. The fluid supplied to each layer 310, 320, 330 of the platen 112 is ultimately supplied to the associated zone of the polishing pad 110. For example, the amount of fluid supplied to the relatively outer periphery of the pad 110 can be increased by increasing the flow of fluid supplied to the layer 310. Similarly, the amount of fluid supplied to layer 310 can be reduced to reduce the amount of fluid present on the relatively outer periphery of polishing pad 110.

  The expansion layer 340 includes any number of similar holes or other paths to accommodate fluid flow from each of the lower fluid distribution layers 310, 320, 330. Layer 340 may also include additional holes or other passages 343 to accommodate probe placement, fluid ejection, and / or other functions as needed. The expansion layer 340 is not shown in FIG. 3, but is also described below in connection with FIG. 4 to further improve the distribution and spreading of the slurry or other fluid across the surface of the pad 110. A distribution extension path as described above.

  During operation, therefore, the fluid supplied to each layer 310, 320, 330 is ultimately distributed to a particular zone of the polishing pad 110 that is commensurate with each. For example, fluid supplied to the layer 310 is distributed radially outward from the source 314 toward the distribution point 317 through the path 312. The fluid then passes from point 317 through hole 325 in layer 320, hole 335 in layer 330, and hole 345 in layer 340 and finally reaches polishing pad 110. The fluid supplied to the layer 320 is also supplied radially outward from the source 324 toward the distribution point 327 through the path 322, and this fluid is then the hole 336 in the layer 330 and the hole 346 in the layer 340. And is guided to the pad 110. The path 332 in the layer 330 similarly directs the fluid supplied to the layer 330 from the source 334 through the path 332 to the distribution point 337 and the holes 347 in the layer 340 guide the fluid toward the pad 110. Fluid is expelled from the pad 110 through the path formed by the holes 303, 313, 323, 333 and 343 as needed.

  The exemplary embodiment of FIG. 3 shows three fluid distribution layers 310, 320, 330 corresponding to three zones of polishing pad 110 (eg, zones 315-318 of FIG. 1), but one or more fluids Any number of zones can be provided by the addition or reduction of distribution layers. Further, the number and location of fluid distribution points in one or more layers can be adjusted up or down and up and down, respectively, in other embodiments, and in practice such numbers and shapes can be adjusted to multiple layers in one embodiment. Can vary between. Accordingly, many changes can be made to the general structure described herein and shown in FIG. 3 without departing from the general concept of multi-zone delivery.

  Fluid distribution can be further improved by including an additional distribution mechanism in the expansion layer 340. Referring now to FIG. 4, the expansion structure 400 may include any suitable number of extensions extending from the central point 402 to the distribution points 410, 411, 412, 413, 414, 415, 416, 417, 418 (respectively). Routes 404, 405, 406, 407, 408, 409 are included. In various embodiments, the central point 402 is in one or more path holes (eg, holes 345, 346, 347 in FIG. 3) that receive fluid from one or more lower fluid distribution layers 310, 320, 330. Correspond. Each path 404-409 thus properly guides fluid received through the path holes 345-347 to cover the wider surface of the polishing pad 110 (FIGS. 1 and 3). The distribution points 410-418 need not be enlarged areas as illustrated in FIG. 4, but rather these points 410-418 merely represent the end points of the corresponding paths 404-409, respectively. A structure similar to the structure 400 typically requires that additional passage holes 345-347 be formed to achieve equal fluid distribution, but alternatively on each fluid distribution layer 310, 320, 330 Note that can be provided. It should also be noted that the overall layout of structure 400 may be radically different in other embodiments. For example, instead of six extended paths 404-409, alternative embodiments may have one or more paths extending from any central point 402. The various paths 404-409 need not be equally spaced from one another as illustrated in FIG. 4, and need not have the same length. Therefore, the “center point” 402 does not necessarily have to be placed at the “center” of the geometry of the structure 400, and may be placed at any convenient point as determined by the particular embodiment. Can do. It is also noted that the expansion paths 404-409 need not be straight as illustrated in FIG. 4 but can be bent or otherwise formed to allow fluid distribution across the surface of the pad 110. I want. Fluid can be routed, for example, around holes 343-344, or otherwise to areas of pad 110 that may be difficult to reach in the underlying pathway holes. The exemplary structure 400 shown in FIG. 4 can thus be configured in various ways to implement a wide variety of equivalent embodiments.

Turning now to FIG. 5, a typical plug suitable for use as the fluid source 352 of the platen 112 (FIG. 3) is shown. Plug 352 suitably receives fluid via any number of fittings 502, 504, 506, 508, each fitting providing fluid to one or more fluid distribution sections 50 9 , 510, 512. In various embodiments, each section 50 9 , 510, 512 has one or more openings 518, 520, 522 that act as a fluid source to a distribution path (eg, paths 312, 322, 332 in FIG. 3). It includes an internal path that interconnects to one of the connection fittings 502-508 provided.

  In the embodiment shown in FIG. 5, each fitting 502-508 is an independent fitting that can receive a supply line or other connection to a fluid source. The amount of fluid ultimately provided to each zone 115-118 (FIG. 1) can be controlled as needed by controlling the amount of fluid supplied and / or the flow rate supplied to the supply line. it can. Each fitting 502-508 can be designed in any convenient manner and any suitable material (eg, aluminum, titanium or other metal) can be used. In various embodiments, each fitting 502-508 has a barbed end for receiving a tube or other fluid distribution line and a reverse taper or other suitable insertion that can be inserted into the plug 352 as required. Including the end of the shape. In various embodiments, as described more fully below, each fitting 502-508 is coupled to the plug assembly 352 via a bushing or other receiving member. Alternatively, each connection fitting 502-508 can be integrally formed with the plug 352 by casting or any method.

Sections 50 9 , 510, 512 can similarly be formed in any manner using any convenient material. In various embodiments, sections 50 9 , 510, 512 can be cast or otherwise formed of aluminum, titanium, or other metal, but equally use plastic, ceramic, carbon fiber, and / or the like. obtain. The plurality of sections are suitably designed such that the openings 518, 520, 522 coincide with the corresponding distribution paths 312, 322, 332. It should be noted that although FIG. 5 shows a plug 352 that is circular, alternate embodiments may have any other shape or size. The various sections 50 9 , 510, 512 can be coupled together and / or to the fittings 502-508 by any method such as, for example, any type of adhesive or other binding.

FIG. 6 shows a more detailed cross-sectional view of the fluid distribution mechanism inside the plug 352. Referring now to FIG. 6, each section 50 9 , 510, 512 has (each) a path 604 extending from a fluid delivery fitting (eg, fitting 602) to openings 518, 520, 522 on the outer peripheral surface of plug 352. , 606, 608. In the cross-sectional view of FIG. 6, fluid that is routed to a particular zone (eg, any of zones 115-118) is delivered through fitting 502 to path 604, which is also on the outer peripheral surface of plug 352. Connect to opening 518. The paths 606 and 608 similarly extend from the fittings 504 and / or 506 to the openings 520 and 522, respectively. FIG. 6 also shows an optional bushing 602 that facilitates insertion and coupling of the fittings 502 to the plug 352. In various embodiments, the various sections 50 9 , 510, 512 can be any suitable adhesive such as polymer adhesives and the like (eg, adhesives that prevent fluid leakage from the paths 604, 606, 608). Combined using Plug 352 also extends vertically through plug 352 to allow bolts, screws, or other attachment members to connect plug 352 to platen assembly 112 (FIG. 3), if desired. It can be formed with one or more through holes (eg, holes 610) that extend.

  During operation, slurry or other fluid can be provided across the polishing surface of pad 110 to any number of fluid delivery zones 115-118 in any manner. As shown in the exemplary embodiment illustrated in FIG. 7, fluid may be any number of valves or other fluids from tanks or other sources 715 to supply lines 732, 734, 736, respectively. It is provided to the polishing pad 110 via the controllers 710, 712, 714. These supply pipes 732, 734, 736 are connected to the fittings 502, 504, 506 of the plug 352, and the fittings sequentially supply fluids to the paths 332, 322, 312 of the distribution layers 310, 320, 330 (respectively). provide. The fluid then passes through the passage holes of the various distribution layers 320, 330 towards the expansion layer 340, where the various expansion structures 400A-F increase the coverage area of each zone. In the exemplary embodiment shown in FIG. 7, the fluid provided by the supply line 732 ultimately provides a zone 1168 on the polishing pad 110. Fluid from supply lines 734 and 736 similarly provide zones 117 and 118, respectively.

  By adjusting the fluid flow rate (or equivalently the fluid flow rate) in the supply lines 732, 734, 736, the amount of fluid distribution to each zone 116, 117, 118 can be adjusted individually. One technique for fluid control includes the use of a digital controller 722, which can be any microprocessor, microcontroller, programmable logic and / or other controller as desired. . In various embodiments, the controller 722 may be a digital memory to implement any suitable control scheme for polishing / planarizing a wafer or other workpiece 108 (FIG. 1) in any desired manner. , Input / output, etc. (or communicate with them). In particular, the controller 722 can include input / output pins, etc., that can provide control signals 716, 718, 720 to the fluid controllers 710, 712, 714, respectively. In various embodiments, the control signals 716, 718, 720 are simply digital or analog signals used to control the fluid flow rates of the supply lines 732, 734, 736, respectively. In one embodiment, fluid controllers 710, 712, 714 are digitally controlled valves that open and close in response to received digital signals (eg, control signals 716, 718, 720). By controlling the duty cycle of the applied signal, the fluid velocity allowed by the valve can be controlled (eg, in a manner similar to pulse code modulation (PCM)). A 60 percent duty cycle of signal 716 can, for example, result in valve 710 being kept open for 60% of any particular time period. The particular time may vary from these ranges in other embodiments, but can be any time ranging from a fraction of a second to a few seconds. Increasing or decreasing the duty cycle of signal 716 has an increasing or decreasing effect on the fluid velocity through supply line 732. The fluid flow rate through the supply lines 734, 736 could be adjusted equally by adjusting the duty cycle (or other characteristic) of the signals 718, 720, respectively.

  In various embodiments, one or more eddy current probes 702 and / or endpoint detection probes 704 can also be present in the platen assembly 112. In such an embodiment, each probe 702, 704 generally provides a data report signal 706, 708 to the controller 722, respectively. Such information can be used in any way, for example, the data 706 received from one or more eddy current probes 704 is the amount of fluid provided to one or more zones 116-118. Can be used to adjust. Such adjustments can be used, for example, to increase or decrease the shear friction of any part of the pad, to reduce the hydroplaning effect and / or for all other purposes. The optical or other endpoint detector 704 also controls the controller 722 to determine when polishing / planarization is complete, i.e., to verify non-uniformity across the surface of the workpiece 108. It can be provided to generate data 708 that can be supported. Probes 702 and 704 can be incorporated into platen 112 by any conventional method, and in various embodiments, different layers 302, 310, 320, 330, 340 can accommodate probes 702 and 704 of any size. A hole or other recess may be included for the purpose. In some embodiments, probe bushings can also be provided to couple with the platen assembly 112 if desired.

  Accordingly, the controller 722 controls the flow of fluid from the source 715 to the pad 110 in any manner. In various embodiments, the controller adjusts the amount of fluid supplied to the zones 116, 117, 118 to produce the required results during polishing / planarization. The controller 722 can also provide one or more control signals 724 that can be used to regulate the pressure applied to the pad 110 or any portion of the pad 110. In various embodiments, the pressure applied to each zone 116-118 can be adjusted to balance the amount of fluid supplied to the zone 116-118. The pressure can be applied from either side of the workpiece 108 (eg, by the carrier head 106 and / or by the platen 112) in embodiments that provide such a function. If desired, the controller 722 can provide an output signal 726 to the system controller or output device.

  Referring now to the last FIG. 8, an exemplary process 800 for properly performing chemical mechanical polishing / planarization on the workpiece 108 (FIG. 1) includes the process target via each fluid delivery zone. Initiating chemical mechanical polishing of the workpiece to provide fluid to an object (step 802) and adjusting, for each fluid delivery zone, the amount of fluid provided through the delivery zone (step 810) Including each wide step. Process 800 may be performed in any manner. In various embodiments, the various steps of process 800 are performed with computer-executable instructions that reside in a memory or other storage medium and execute on a digital computer system (such as controller 722 of FIG. 7). The various process steps shown in FIG. 8 are merely logical steps that can be performed as part of one typical process, and in fact the steps are organized differently and differ. Can be ordered, refilled, or otherwise modified in any way. In particular, the various process steps need not be performed in the temporal order shown in FIG.

  The initiation of chemical mechanical polishing / planarization can be performed in any manner (step 802). In various embodiments, a slurry or other fluid is initially routed to each of the various zones 115-118 (FIG. 1) on the pad 110, and the relative motion of the workpiece 108 and / or the pad 110 is determined by which Such an annular, rotational and / or other method is also initiated. During polishing, the amount of fluid provided to each of the various zones 115-118 (step 802) can be adjusted by any method. In the exemplary embodiment of FIG. 8, fluid flow is adjusted for each zone based on the data from which data was received and / or calculated (step 810). For example, step 806 can receive data from any type of probe (eg, probes 702 and 704 in FIG. 7) and process this data (data 706, 708) in any manner. Show that you can. For example, if a significant eddy current is observed in a particular area of the pad 110, the fluid delivered to that area is reduced (or otherwise adjusted) until the current decreases.

  The specific amount or flow rate of the fluid can be calculated, or any method (step 808) can be applied. In various embodiments, the nominal flow rate of polishing is set at the beginning of polishing by adjusting its increase and decrease so that the flow is appropriate. The flow rate can be expressed and set in any way. In an exemplary embodiment, the requested flow rate is mathematically calculated using conventional data processing techniques, and the resulting values are then controlled by control signals 716, 718, 720 (FIG. 7). Converted to a similar suitable representation that can be applied as or that the actual adjustment of the fluid flow (step 810) can be performed. For example, the PCM technology described above could be used to open and close a conventional digital valve, thereby adjusting the flow rate of the fluid supplied to any particular zone 115-118 of the polishing pad 110. Other encoding and implementation schemes could be devised in many alternative embodiments.

  As described above, the pressure applied to one or more zones 115-118 (or the entire pad 110) can be adjusted in any manner (step 812). In various embodiments, pressure can be applied to each of the independently controllable zones 115-118 so that each zone 115-118 receives a controlled pressure in relation to the supplied fluid. Can do. Pressure and fluid flow can be correlated in any way, and fluid flow can increase with increasing pressure, for example, or otherwise be adjusted as appropriate.

  In summary, new systems, apparatus and methods for implementing chemical mechanical polishing / planarization techniques are provided. By providing multiple fluid delivery zones, each of which can be independently controlled, increased surface uniformity can be obtained and / or additional performance enhancement can be provided.

While at least one exemplary embodiment has been presented in the foregoing detailed description, it should be appreciated that a vast number of variations exist. It should also be understood that the exemplary embodiment or exemplary embodiments are only examples and are not intended to limit the scope, applicability, or form of the invention in any way. I will. Rather, the foregoing detailed description will provide those skilled in the art with convenient guidance for implementing an exemplary embodiment or exemplary embodiments. It will be understood that various changes may be made in the function and arrangement of components without departing from the scope of the claims appended hereto and the legally equivalent scope of the invention.
Application Example 1: A polishing pad having a polishing surface and a platen disposed proximate to the polishing pad and including a plurality of fluid distribution layers, each of the fluid distribution layers from a fluid source on the fluid distribution layer Each of the plurality of fluid distribution layers corresponds to a different location on the polishing surface, thereby providing a plurality of fluid delivery zones on the polishing pad. A chemical mechanical polishing apparatus is formed.
Application Example 2: Application wherein the fluid distribution layers are stacked on one another and the second fluid distribution layer includes holes that coincide with the distribution points of the first fluid distribution layer proximate to the second fluid distribution layer Apparatus according to Example 1.
Application Example 3: The fluid distribution layers are stacked on each other, and each fluid distribution layer interposed between the first fluid distribution layer and the polishing pad corresponds to the distribution point of the first fluid distribution layer. The apparatus of application 1, wherein a hole is formed, whereby a path is formed from the distribution point of the first fluid distribution layer and a portion of the polishing pad.
Application Example 4: The apparatus according to Application Example 1, wherein the fluid source includes a plug displaced in the fluid distribution layer.
Application Example 5: The apparatus according to Application Example 4, wherein the plug includes a plurality of fluid distribution sections, each of the plurality of sections including an opening corresponding to a path of the fluid distribution layer of one of the fluid distribution layers. .
Application Example 6 The apparatus according to Application Example 5, wherein the fluid distribution section includes an internal path in fluid communication with the opening.
Application Example 7: The plug further includes a plurality of connection fittings, each having a central path that couples one internal path of the fluid distribution section to one of a plurality of fluid distribution lines. The device according to application example 5.
Application Example 8: The apparatus of Application Example 7, further comprising a controller configured to regulate the fluid flow provided by each of the plurality of fluid delivery lines.
Application Example 9: The platen further includes an expansion layer displaced between the plurality of fluid distribution layers and the polishing pad, each expansion layer corresponding to one of the distribution points of the fluid distribution layer. The device according to application example 1 including a plurality of passage holes.
Application Example 10: The apparatus according to Application Example 8, wherein the extension layer further includes a plurality of extension paths extending radially outward from each of the path holes.
Application Example 11 A platen used for chemical mechanical polishing of an object to be processed, the first fluid distribution layer including a first path extending radially from a first fluid source to a first distribution point; A second fluid distribution layer including a second path extending radially from a second fluid source to a second fluid distribution point and proximate to the first fluid distribution layer; and the second fluid distribution layer An expansion layer proximate to the first fluid distribution layer, wherein the second fluid distribution layer includes a hole that coincides with the first distribution point in the first fluid distribution layer, and the expansion layer includes the second fluid distribution layer. A platen comprising: a first passage hole that coincides with a hole in the fluid distribution layer; and a second passage hole that coincides with the second fluid distribution point.
Application Example 12: The platen of Application Example 11, wherein the first and second fluid distribution layers are adapted to receive plugs providing the first and second fluid sources.
Application Example 13: The plug has a first layer configured to send fluid from the first connection fitting to the first fluid source, and fluid from the second connection fitting to the second fluid source. A platen according to application example 12, including a second layer configured to deliver.
Application Example 14: The platen according to Application Example 11, wherein the expansion layer further includes a plurality of expansion paths extending radially outward from each of the first and second path holes.
Application Example 15: Method of chemical mechanical polishing a workpiece using a platen having a plurality of fluid delivery zones, wherein the workpiece is provided to provide fluid to the workpiece through each of the plurality of fluid delivery zones A chemical mechanical polishing method, wherein during the chemical mechanical polishing of the workpiece, the amount of fluid supplied through the fluid delivery zone is adjusted for each fluid delivery zone.
Application Example 16: The method of Application Example 15, wherein the amount of fluid provided to each of the plurality of zones is adjusted independently of the amount of fluid provided to the other zones.
Application Example 17: The method of Application Example 15, further comprising stopping fluid delivery in at least one of the fluid delivery zones, but continuing fluid distribution in at least one other of the fluid delivery zones .
Application Example 18: The method of Application Example 15, wherein the amount of fluid provided through at least one of the plurality of zones is adjusted in response to data received from a probe.
Application Example 19: The method of Application Example 15, wherein the amount of fluid provided through at least one of the plurality of zones is adjusted in relation to the applied pressure.
Application 20: The method of application 15, further comprising adjusting a pressure applied to at least one of the plurality of fluid delivery zones during chemical mechanical polishing of the workpiece.

110 polishing pad 112 platen 115, 116, 117, 118 fluid distribution zone 310, 320, 330 fluid distribution layer 312, 322, 332 fluid distribution path 317, 327, 337 distribution point 325, 335, 336 hole 345, 346, 347 path Hole 352 Plug (fluid source)
404, 405, 406, 407, 408, 409 Extended path 50 9 , 510, 512 Fluid distribution section 502, 504, 506, 508 Connection fitting 518, 520, 522 Opening 722 Control device

Claims (10)

  A polishing pad having a polishing surface and a platen disposed proximate to the polishing pad and including a plurality of fluid distribution layers, each of the fluid distribution layers from a fluid source to a distribution point on the fluid distribution layer. Including an extended fluid distribution path, each distribution point of the plurality of fluid distribution layers corresponding to a different location on the polishing surface, thereby forming a plurality of fluid delivery zones in the polishing pad; Chemical mechanical polishing equipment. The fluid distribution layers are stacked on each other, and each fluid distribution layer interposed between the first fluid distribution layer and the polishing pad has a hole corresponding to the distribution point of the first fluid distribution layer. The apparatus of claim 1, wherein a path is formed from the distribution point of the first fluid distribution layer to a portion of the polishing pad. Wherein the fluid source comprises a plug, the plug comprises a plurality of fluid distribution section, and each of the plurality of sections including openings corresponding to the path of one of said fluid distribution layer of the fluid distribution layer according to claim 1, The device described in 1.   The platen further includes an expansion layer displaced between the plurality of fluid distribution layers and the polishing pad, the expansion layer being a plurality of paths each corresponding to one of the distribution points of the fluid distribution layer. The apparatus of claim 1 including a hole. The apparatus of claim 4 , wherein the expansion layer further includes a plurality of expansion paths extending radially outward from each of the path holes.   A platen used for chemical mechanical polishing of a workpiece, the first fluid distribution layer including a first path extending radially from a first fluid source to a first distribution point; A second fluid distribution layer proximate to the first fluid distribution layer including a second path extending radially from a fluid source to a second fluid distribution point; and an extension proximate to the second fluid distribution layer And the second fluid distribution layer includes a hole that coincides with the first distribution point in the first fluid distribution layer, and the expansion layer includes the second fluid distribution layer. A platen including a first passage hole that coincides with the second fluid distribution point and a second passage hole that coincides with the second fluid distribution point. The platen of claim 6 , wherein the first and second fluid distribution layers are adapted to receive plugs that provide the first and second fluid sources. The plug is configured to send a fluid from a first connection fitting to the first fluid source and a first layer configured to send fluid from the second connection fitting to the second fluid source. The platen according to claim 7 , comprising a second layer formed. The platen of claim 6 , wherein the extension layer further includes a plurality of extension paths extending radially outward from each of the first and second path holes. A method for chemical mechanical polishing a workpiece using a platen having a plurality of fluid delivery zones, wherein the platen includes a plurality of fluid distribution layers, each of the fluid distribution layers from a fluid source on the fluid distribution layer. includes a fluid distribution path that extends to the distribution point of the respective pre-SL component Scoring of the plurality of fluid distribution layers correspond to different locations on the polishing surface, a plurality of fluid delivery zones are formed on the polishing pad by which ,
The method
Independently providing fluid to the workpiece through each of the plurality of fluid delivery zones; and during the chemical mechanical polishing of the workpiece, the amount of fluid supplied through the fluid delivery zones is determined by the fluid Chemical mechanical polishing method that adjusts independently for each delivery zone.

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